Paul Wessel

The 2020 Ian McHarg Medal is awarded to Paul Wessel for outstanding contributions to developing open-source software, including Generic Mapping Tools (GMT), for the Earth and space sciences that have enabled thousands of research projects and papers.

The committee was unanimous in recommending Paul Wessel for the 2020 McHarg Medal in recognition of his outstanding contributions to developing open source software for the Earth and Space science community that has enabled thousands of research projects and publications around the globe. The most prominent is the extensively used Generic Mapping Tools (GMT), which was first released as open source software in 1991: Wessel has been the founder and most active developer.
Originally developed for marine Gravity, Magnetic and Topography data, it enables the analysis, display and interpretation of marine geological and geophysical data in both 2D and 3D, and in various kinds of map projections. GMT now has 30,000+ users worldwide who manipulate and display profile, gird and image data and has been supported by the National Science Foundation since 1993. Its wide usage in different domains shows that although it was designed to address specific requirements from the Earth and space science community, GMT was further developed for additional science-use cases. Besides its excellent visualisation capabilities, the software includes tools for processing and manipulating multi-dimensional datasets. Not only has GMT adapted to new-use cases, the underpinning technology has been continually upgraded as new enabling technologies have been developed: in particular, Wessel has shown a sustained dedication to improving and updating the GMT API so that it now allows MATLAB, Octave, Python and Julia interfaces to be developed.

Under Wessel’s leadership, GMT has evolved into a general-purpose tool that is no longer focussed on a single domain and application and is regarded as the ‘glue’ for collaborative solid Earth and planetary research. GMT truly is a major contribution to Earth and space science informatics, a pioneering effort in the development of open source software that still remains relevant today and will continue to do so into the future.

Wessel’s publication and citation record pertaining to the GMT software is impressive and includes a list of 15 papers in which GMT played a prominent role and has enabled high-impact research across the Earth and space science community. One referee stated that Wessel “literally transformed the way marine geophysics was performed”.

Given that the McHarg Medal honours the pioneer of Geographic Information Systems, it is fitting that the 2020 medal is awarded to Paul Wessel, developer of algorithms and open source software tools that have enabled so many researchers to process large amounts of disparate, geographically located data into valuable scientific information that in turn has underpinned many high-impact scholarly publications.